U.S. patent number 4,955,651 [Application Number 07/450,577] was granted by the patent office on 1990-09-11 for hook latch adapter.
This patent grant is currently assigned to Cooper Industries, Inc.. Invention is credited to Donald E. Barber.
United States Patent |
4,955,651 |
Barber |
September 11, 1990 |
Hook latch adapter
Abstract
An adapter for attaching a universal latch to a hook. The
adapter consists of a spring formed into two helical end coils
connected by an U-shaped intermediate section. The adapter fits
over a flange on the hook with the end coils in axial alignment
with a latch mounting hole through the flange. The end coils fill
excess space between the flange and the latch and center the latch
on the flange.
Inventors: |
Barber; Donald E. (Marathon,
NY) |
Assignee: |
Cooper Industries, Inc.
(Houston, TX)
|
Family
ID: |
23788647 |
Appl.
No.: |
07/450,577 |
Filed: |
December 11, 1989 |
Current U.S.
Class: |
294/82.19;
24/599.8 |
Current CPC
Class: |
B66C
1/36 (20130101); Y10T 24/45356 (20150115) |
Current International
Class: |
B66C
1/22 (20060101); B66C 1/36 (20060101); B66C
001/36 () |
Field of
Search: |
;294/82.17,82.19,82.2,82.22
;24/241R,241S,241P,241PP,241PL,241SP,241,SB ;411/544,546,342,343
;267/155,275 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
Catalog Sheet Showing the Safe-T-Latch Manufactured by Industrial
Safety & Security Co..
|
Primary Examiner: Focarino; Margaret A.
Assistant Examiner: Kramer; Dean J.
Attorney, Agent or Firm: MacMillan, Sobanski & Todd
Claims
I claim:
1. For a hook having a throat and a flange adjacent said throat,
said flange having a predetermined thickness and a hole
therethrough for mounting a latch, a latch having two sides, said
sides having aligned holes and having a predetermined spacing
greater than said predetermined thickness, a latch return spring,
and fastening means extending through said side holes and said
flange hole for securing said latch and said return spring on said
flange with said latch sides located on opposite sides of said
flange, a hook latch adapter comprising first and second spacers,
said spacers defining holes for passing said fastener means, and a
generally U-shaped wire loop connecting said spacers together with
said spacer holes aligned and said spacers axially spaced apart by
substantially the predetermined thickness, said spacers when
positioned on opposite sides of a hook flange with said spacer
holes aligned with the flange hole having a maximum axial dimension
no greater than the predetermined latch side spacing.
2. A hook latch adapter, as set forth in claim 1, wherein said
spacers are in the form of helical wire windings integrally formed
with said U-shaped loop.
3. A hook latch adapter, as set forth in claim 2, wherein said
helical windings are shaped to conform with the surface of a hook
flange.
4. A hook latch adapter, as set forth in claim 2, wherein said
adapter has a maximum axial dimension substantially equal to the
predetermined latch side spacing.
5. A hook latch adapter, as set forth in claim 2, wherein said two
helical wire windings have substantially the same axial length for
centering the latch on the hook flange.
Description
TECHNICAL FIELD
The invention relates to hooks such as eye hoist hooks, shank hoist
hooks, swivel hoist hooks and the like, and more particularly to an
adapter for installing a universal swivel latch on a hook.
BACKGROUND ART
Hooks are used for many applications, such as for hoisting loads. A
hook comes with either a fixed or a swivel eye or with other means
for attachment to, for example, a cable or a chain. The hook is
forged from a metal selected to meet application requirements, such
as strength, corrosion resistance, etc. The hook is formed with a
throat which is open to engage a load.
For some applications, it is desirable to provide a latch for
closing the hook throat to retain the load in the hook. One common
type of latch is attached to a cam or flange formed on the hook
adjacent the throat opening. The flange is provided with a hole for
attachment of the latch. A spring and holes in the latch are
aligned with the flange hole and a bolt is secured through the
aligned holes and spring. The spring urges the latch to a position
closing the hook throat, while permitting the latch to be pivoted
to an open position where the throat is clear for engaging or
disengaging a load.
Because of the environment in which hooks are used, the latch may
break or become damaged. Therefore, it is common for the hook
manufacturers to provide replacement latches for hooks. However,
each hook manufacturer makes hooks of its own design. There are no
dimension standards for hooks purchased from different
manufacturers. This is particularly true for the thickness of the
flange on which a latch is mounted. Consequently, a hook latch made
for one manufacturer's hooks will not necessarily fit a hook from
another manufacturer.
DISCLOSURE OF INVENTION
According to the invention, an adapter is provided for attaching a
universal hook latch to hooks having different dimensions for the
latch mounting flange. The adapter consists of a wire spring having
two helical end coils connected by a U-shaped intermediate section.
The intermediate section has a width and shape for fitting over the
hook flange and for holding the two end coils in axial alignment
with the mounting hole in the flange. The latch spring and latch
are positioned over the adapter and flange and attached with a bolt
as with a conventional prior art latch. The end coils on the
adapter are of the same axial dimension to center the latch on the
flange. Further, the end coils on the adapter are sized to fill
excess space between the flange and the latch.
Accordingly, it is an object of the invention to provide an adapter
for attaching a universal latch to a flange on a hook.
Other objects and advantages of the invention will be apparent from
the following detailed description of preferred embodiments of the
adapter and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is side elevational view through an eye hook with an
attached latch;
FIG. 2 is an enlarged end view of the latch from FIG. 1;
FIG. 3 is a top view of the latch of FIG. 2;
FIG. 4 is a side view of the latch of FIG. 2;
FIG. 5 is an enlarged perspective view of a latch closure
spring;
FIG. 6 is a side view of a hook latch adapter according to one
embodiment of the invention;
FIG. 7 is an end view of the adapter of FIG. 6;
FIG. 8 is an enlarged fragmentary perspective view showing the
adapter positioned on a hook flange;
FIG. 9 is an enlarged fragmentary cross sectional view as taken
along line 9--9 of FIG. 1 and showing a latch attached to a hook
with the adapter of FIG. 6;
FIG. 10 is a side view of a modified embodiment of the hook latch
adapter of the invention; and
FIG. 11 is a fragmentary cross sectional view, similar to FIG. 9,
but showing a latch attached to a hook with the modified adapter of
FIG. 10.
BEST MODE FOR CARRYING OUT THE INVENTION
Referring to the drawings and particularly to FIG. 1, an exemplary
eye hook 15 is shown with an attached latch 16. The hook 15 is
formed with an eye 17 for attachment, for example, to a cable or a
chain (not shown). A hook section 18 depends from the eye 17 and
terminates at a free end 19. The hook section 18 has a throat 20
which is closed by the latch 16. A cam or flange 21 extends from
the eye 17 and the hook section 18 adjacent the throat 20 for
securing the latch 16 to the hook 15.
The latch 16 and a latch spring 22 are secured to the flange 21 by
a bolt 23. The latch 16 is free to swing or pivot about the axis of
the bolt 23. The spring 22 urges the latch 16 to the position shown
in FIG. 1 wherein a free end 24 of the latch 16 contacts a surface
region 25 of the hook section 18 near the free end 19 to close the
hook throat 20. However, the latch 16 may be pivoted against the
force of the spring 22 to a position where the free latch end 24
abuts a surface region 26 on the hook section 18 to open the throat
20 for engaging or disengaging a load (not shown) on the hook
15.
FIGS. 2-4 show details for an exemplary latch 16. The latch 16 is a
generally U-shaped channel having a top web 27 and two spaced sides
28 and 29. At one end 30, the sides 28 and 29 have aligned openings
31 for passing the bolt 23 (FIG. 1) and the web 27 has a relieved
area 32 for clearing the flange 21 as the latch 16 is pivoted. At
an opposite end 33, the web 27 may be provided with a curve 34 for
confirming to the hook surface region 25.
The latch spring 22 is shown in detail in FIG. 5. The spring 22 is
formed from a wire bent into two loops 36 and 37. The loops 36 and
37 are connected together by a U-shaped bend 38 which holds the
loops 36 and 37 spaced apart, parallel and in axial alignment for
passing the bolt 23. A leg 39 extends from the loop 36 and a leg 40
extends from the loop 37. The loops 36 and 37 are spaced apart
slightly less than the spacing between the latch sides 28 and 29.
When the latch 16 is attached to the hook flange 21, the loops 36
and 37 are located on opposite sides of the flange 21 and the bolt
23 extends through the loops 36 and 37. As will be seen in FIG. 1,
the U-shaped bend 38 pressed against the flange 21 and the legs 39
and 40 press against the latch web 27 to urge the latch 16 to the
closed position.
In the past, the latch 16 has been designed for a hook having
specific dimensions for the flange 21. The loops 36 and 37 on the
spring 22 were spaced apart to just fit over the flange 21 and the
sides 28 and 29 on the latch 16 were spaced to just fit over the
spring loops 36 and 37. This construction centered the latch 16 on
the flange 21 and prevented the latch from significant sideways
movement on the flange 21. However, it also meant that a latch 16
designed for a hook having a flange with a predetermined thickness
could not be used on a hook with a flange having a different
thickness. If the latch was too wide for the hook flange it had
excessive sideways movement relative to the flange.
According to the invention, a latch 16 is designed to fit hooks
having latch mounting flanges with different thicknesses. The latch
16 is formed with its sides 28 and 29 spaced and the spring 22 is
formed with the loops 36 and 37 spaced to accommodate the thickest
hook flange 21. When the latch 16 is used with a hook having a
thinner flange 21, the excess space between the hook flange 21 and
the latch sides 28 and 29 is filled with an adapter 41, as shown in
FIGS. 6 and 7. Preferably, the adapter 41 is wound from wire and
includes two helical windings 42 and 43 connected by a generally
U-shaped loop 44. The loop 44 holds the windings 42 and 43 spaced
apart and in axial alignment. The spacing between the windings 42
and 43 is substantially the same as the flange thickness for a hook
on which the adapter 41 is to be used to mount the latch 16. By
"substantially the same as the flange thickness", it is to be
understood that the winding spacing may be slightly less than the
flange thickness provided the resiliency of the loop 44 permits
pushing the adapter 41 on the flange, or it may be the same as the
flange thickness, or it may be slightly greater than the flange
thickness provided it does not permit excessive sideways movement
of the latch 16 on the flange 21. The windings 42 and 43 are formed
with an inside diameter sufficient to pass the bolt 23 or other
fastener attaching the latch 16 to the hook 15. Preferably, the
windings 42 and 43 have substantially the same axial length for
centering the latch 16 on the hook flange 21.
FIG. 8 shows the adapter 41 positioned over the hook flange 21. The
windings 42 and 43 are positioned on opposite sides of the flange
21 in alignment with a latch mounting hole 45 through the flange
21. The loop 44 wraps around the flange 21 to connect the windings
42 and 43. By connecting the windings 42 and 43 together, the latch
is more easily mounted on the flange than if separate spacers were
used to center the latch 16 on the flange 21.
FIG. 9 is a fragmentary cross sectional view showing the latch 16
mounted on the hook flange 21 with the adapter 41. The bolts 23
extends sequentially through the latch side 28, the spring loop 36,
the adapter winding 42, the flange hole 45, the adapter winding 41,
the spring loop 37 and the latch side 29. A self locking nut 46
secures the bolt 23 on the latch 16. It should be appreciated that
although the adapter winding 41 is shown positioned between the
spring loop 37 and the flange 21 and the adapter winding 42 is
shown positioned between the spring loop 36 and the flange 21, the
windings 41 and 42 may extend between the latch sides 29 and 28 and
the flange 21, respectively. In that case, the spring loop 37 would
be positioned coaxially over the winding 41 and the spring loop 36
would be positioned coaxially over the winding 42. In either case,
the windings 41 and 42 are spacers sized to take up excess space
between the latch sides 28 and 29 and the flange 21 and to center
the latch 16 on the flange 21.
FIG. 10 shows a modified adapter 49 suitable for use with a
modified hook flange 50 as shown in FIG. 11. The flange 50 has a
predetermined thickness between two sides 51 and 52. A nipple 53
extends from the side 51 and a nipple 54 extends from the side 52.
A latch mounting hole 55 extends between the sides 51 and 52
coaxially through the nipples 53 and 54. The adapter 49 is wound
from a wire and has a helical winding 56 and a helical winding 57
connected by a U-shaped loop 58. The loop 58 supports the windings
56 and 57 in axial alignment and spaced apart by substantially the
thickness of the flange 50. The winding 56 has a large diameter
portion 59 adapted to fit over the nipple 53 connected to a smaller
diameter portion 60 adapted to fit between the nipple 53 the side
29 of the latch 16. Similarly, the winding 57 has a large diameter
portion 61 adapted to fit over the nipple 54 connected to a smaller
diameter portion 62 adapted to fit between the nipple 54 and a side
28 of the latch 16. FIG. 11 shows a latch spring 63 having a loop
64 of a diameter for fitting coaxially over the adapter winding 60
adjacent the latch side 29 and a loop 65 of a diameter for fitting
coaxially over the adapter winding 62 adjacent the latch side 28.
Whether the spring loops fit over the adapter windings as in FIG.
11 or between the adapter windings and the latch sides as in FIG.
9, the adapter windings 56 and 57 are sized to take up excess space
between the latch sides 28 and 29 and the flange 21 or 50 and to
center the latch 16 on the flange.
In the broadest aspect of the invention, the windings 42 and 43 on
the adapter 41 can be replaced with spacer tubes secured to and
connected by the U-shaped wire loop 44. However, the preferred
embodiment of the invention uses a single wire formed into the
adapter. The number of turns forming each winding on the adapter
can be varied to accommodate different dimensions for the latch and
the hook flange. It should be appreciated that a single latch may
be sold in a kit with several different dimensioned adapters to
permit use of the latch with several different hooks from different
manufacturers. It also will be appreciated that various other
modifications and changes may be made to the adapters 41 and 49
without departing from the spirit and the scope of the following
claims .
* * * * *